1. Field of the Invention
The present invention relates to an optical module and a method of controlling an optical module.
2. Description of the Related Art
There is known an optical module including a laser module in which a semiconductor laser and an electro-absorption modulator (EAM) element that operates as an optical modulator are integrated. As one example of such an EA element included in the optical module, there is known a cooled EA element that is used while being controlled to have a constant operating temperature regardless of the temperature in the vicinity of the EA element (environmental temperature). The operating temperature of the cooled EA element is relatively high. Therefore, when the environmental temperature decreases, it is necessary to heat the cooled EA element by a thermo-electric cooler (TEC), which requires a large amount of power.
Further, as another example of the EA element included in the optical module, there is known an uncooled EA element. As an example of a technology relating to the uncooled EA element, Japanese Patent Application Laid-open No. 2010-239056 discloses an uncooled-type distributed feedback laser integrated with an electro-absorption modulator that is capable of performing long-distance transmission at high speed. The range of the operating temperature of the uncooled EA element is wide to some extent. Therefore, it is known that, when the uncooled EA element is used as the EA element included in the optical module, as compared to the case where the cooled EA element is used, the optical module can be operated with low power consumption.